Rory Dow alerted me to the fact that similar specimens had been recorded in Vietnam before. Actually from Bach Ma National Park, close to Da Nang, by Matti Hamalainen. And Haruki Karube also mentioned having recorded it. So in the south of Vietnam there is a species with a pale blue face and mine is not just an aberration.
Interestingly, the description in Fraser mentioned that the pale blue extends to the base of the antennae, exactly like in my specimen (the ochre of B. melanothorax extends only marginally unto the frons). Rory mentioned that there are some small differences between the specimens of B. laidlawi from India and those from around Da Nang, for instance by displaying a pale area on S9. This is mentioned also by Asahina. However, the description by Fraser mentions only "Abdomen glossy black or blackish-brown in subteneral specimens, segments 3 to 6 with an obscure yellowish spot or annual near the base." He says noting about a pale area on S9. I have not been able to find any photo or further useful illustration of the species and therefore think it is perfectly possible that the species in Vietnam is in fact B. laidlawi. Nevertheless, given the long distance between it known range and Vietnam, it is better to consider this B. cf. laidlawi until a direct comparison with Indian laidlawi is possible.
|Male Burmargiolestes cf. laidlawi. Note the pale lateral lines on the prothorax, the pale line at the dorsal end of the thoracic sutures and the all dark S8-10.|
|Slightly overexposed face of the same male. The pale blue extends well beyond the base of the antennae and up to the central ocellus. This is much more extensive than in B. melanothorax.|